Just read chapter 7 about the silk roads. Very interesting that there were multiple silk roads, and how they moved trading goods from one place to another, and surprised  on how big the caravans were. How they would have to be careful and watch out for bandits. Also looking at what parts of Eurasia would specialize in certain trades for the silk road, and how disease was spread was also interesting, especially how fast the diseases spread from one place to another.